Tay-Sachs disease, also called Amaurotic Familial Idiocy, hereditary metabolic disorder that causes progressive mental and neurologic deterioration and results in death in early childhood. The disease is inherited as an autosomal recessive trait and occurs most commonly among people of eastern European (Ashkenazic) Jewish origin.

In infants born with the disease, abnormally low activity of the enzymehexosaminidase A allows an unusual sphingolipid, ganglioside GM2, to accumulate in the brain, where it soon exerts devastating effects on neurological function. In some affected children, the enzyme is present but the sphingolipid accumulates nonetheless. Tay-Sachs infants appear normal at birth but become listless and inattentive during the first few months of life. As the disease progresses, the child loses motor abilities already gained, such as crawling and sitting, develops uncontrollable seizures, and is unable to lift its head or swallow. A cherry-red spot develops on the retina, and blindness and a general paralysis usually precede death. There is no treatment for the disease.

About 1 in 2,500 Ashkenazic Jewish infants is afflicted with Tay-Sachs disease, as compared to 1 in 360,000 non-Jewish babies. The disease can be detected by prenatal tests. About 1 in 25 Ashkenazic Jews is a carrier of the Tay-Sachs gene. Adult genetic carriers can be identified by measuring the level of hexosaminidase A in their blood or other fluids.

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member of the Jews who lived in the Rhineland valley and in neighbouring France before their migration eastward to Slavic lands (e.g., Poland, Lithuania, Russia) after the Crusades (11th–13th century) and their descendants. After the 17th-century persecutions in eastern Europe, large numbers...

any person whose religion is Judaism. In the broader sense of the term, a Jew is any person belonging to the worldwide group that constitutes, through descent or conversion, a continuation of the ancient Jewish people, who were themselves descendants of the Hebrews of the Old Testament. In ancient...

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a recessive disorder most common among persons of Middle and Eastern European Jewish origin, and detectable by prenatal tests. Infants appear normal at birth but become listless and inattentive during the first few months of life. An early sign is an exaggerated startle response to sound. Rapidly progressive symptoms include retardation, paralysis, blindness, seizures, and cherry-red retinal spots; death by age 3 is common. Tay-Sachs disease is caused by abnormally low activity of the enzyme hexosaminidase A, resulting in the formation of sphingolipids in the brain